Allow clients to enable or disable all jdbc traces (#56) (#70)

src/main/java/io/opentracing/contrib/jdbc/JdbcTracingUtils.java

@@ -38,7 +38,7 @@ static Span buildSpan(String operationName,
       boolean withActiveSpanOnly,
       Set<String> ignoredStatements,
       Tracer tracer) {
-    if (withActiveSpanOnly && tracer.activeSpan() == null) {
+    if (!TracingDriver.isTraceEnabled() || (withActiveSpanOnly && tracer.activeSpan() == null)) {
       return NoopSpan.INSTANCE;
     } else if (ignoredStatements != null && ignoredStatements.contains(sql)) {
       return NoopSpan.INSTANCE;

src/main/java/io/opentracing/contrib/jdbc/TracingDriver.java

@@ -106,7 +106,22 @@ public synchronized static Driver load() {
     }
   }
 
-  private static boolean interceptorMode = false;
+    private static boolean traceEnabled = true;
+
+    /**
+     * Sets the {@code traceEnabled} property to enable or disable traces.
+     *
+     * @param traceEnabled The {@code traceEnabled} value.
+     */
+    public static void setTraceEnabled(boolean traceEnabled) {
+        TracingDriver.traceEnabled = traceEnabled;
+    }
+
+    public static boolean isTraceEnabled() {
+        return TracingDriver.traceEnabled;
+    }
+
+    private static boolean interceptorMode = false;
 
   /**
    * Turns "interceptor mode" on or off.

src/test/java/io/opentracing/contrib/jdbc/JdbcTracingUtilsTest.java

@@ -0,0 +1,77 @@
+/*
+ * Copyright 2017-2020 The OpenTracing Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
+ * in compliance with the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software distributed under the License
+ * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
+ * or implied. See the License for the specific language governing permissions and limitations under
+ * the License.
+ */
+package io.opentracing.contrib.jdbc;
+
+import io.opentracing.mock.MockSpan;
+import io.opentracing.mock.MockTracer;
+import io.opentracing.util.GlobalTracerTestUtil;
+import org.junit.AfterClass;
+import org.junit.Before;
+import org.junit.BeforeClass;
+import org.junit.Test;
+
+import java.sql.Connection;
+import java.sql.DriverManager;
+import java.sql.Statement;
+import java.util.List;
+
+import static io.opentracing.contrib.jdbc.TestUtil.checkNoEmptyTags;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+
+public class JdbcTracingUtilsTest {
+
+    private static final MockTracer mockTracer = new MockTracer();
+
+    @BeforeClass
+    public static void init() {
+        GlobalTracerTestUtil.setGlobalTracerUnconditionally(mockTracer);
+    }
+
+    @Before
+    public void before() {
+        mockTracer.reset();
+    }
+
+    @AfterClass
+    public static void afterClass() {
+        TracingDriver.setTraceEnabled(true);
+    }
+
+    @Test
+    public void buildSpanWithTracedEnabled() throws Exception {
+        TracingDriver.setInterceptorMode(false);
+        TracingDriver.setTraceEnabled(true);
+        try (Connection connection = DriverManager.getConnection("jdbc:tracing:h2:mem:jdbc")) {
+            Statement statement = connection.createStatement();
+            statement.executeUpdate("CREATE TABLE employer (id INTEGER)");
+        }
+
+        List<MockSpan> spans = mockTracer.finishedSpans();
+        assertEquals(2, spans.size());
+        checkNoEmptyTags(spans);
+    }
+
+    @Test
+    public void buildSpanWithoutTraceEnabled() throws Exception {
+        TracingDriver.setInterceptorMode(false);
+        TracingDriver.setTraceEnabled(false);
+        try (Connection connection = DriverManager.getConnection("jdbc:tracing:h2:mem:jdbc")) {
+            Statement statement = connection.createStatement();
+            statement.executeUpdate("CREATE TABLE employer (id INTEGER)");
+        }
+
+        assertTrue(mockTracer.finishedSpans().isEmpty());
+    }
+}